title: [Analysis of the stability and local cooperativity of DNA: proposal of a molecular mechanism for the initiation of the transcription of gene A3 of bacteriophage T7 by the RNA polymerase from E. coli].
abstract: RNA polymerase (RNAP) complexed to the A3 promoter of bacteriophage T7 is known to unwind a DNA segment located downstream of the Pribnow box. This finding can be accounted for if it is assumed that the subunit sigma of RNAP unstabilizes three GC base pairs located just upstream of the transcription start. As a consequence, the rate of promoter utilisation might be related to the relative stability of the DNA between the "Pribnow box" and the transcription start.
mesh_terms: D001482:Base Composition; D004269:DNA, Bacterial; D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology*; D009691:Nucleic Acid Denaturation; D009876:Operon; D013604:T-Phages / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D004269:DNA, Bacterial; D012321:DNA-Directed RNA Polymerases
vernacular_title: Analyse de la stabilité et de la coopérativité locale de l'ADN: proposition d'un mécanisme moléculaire de l'initiation de la transcription du gène A3 du bactériophage T7 par l'ARN polymérase d'E. coli.